div{
    border:1px solid red;
}
#main{
    width: 900px;
    margin: auto;
}
#head{
    height: 60px;
    font-weight: bold;
    font-size: 20px;
    line-height: 60px;
    vertical-align: middle;
    text-indent: 10px;
}
#nav{
    height: 40px;
    line-height: 40px;
    vertical-align: middle;
    text-indent: 10px;
}
#nav span{
    color: blue;
}
#content{
    height: 230px;
}
#content p{
    text-indent: 10px;
}
#contentfoot{
    text-align: center;
    color: red;
}
#foot{
    height: 120px;
    text-indent: 20px;
}
#foot span{
    color: red;
}